Learn Apex
DML operations
insert, update, delete, upsert, undelete — each has a job. Use list forms to stay bulk-safe.
DML

insert

Create new rows in memory, then persist.

Example
Account a = new Account(Name = 'Acme');
insert a;
Bulk (preferred in triggers)
List<Account> rows = new List<Account>();
// ... fill rows
insert rows;

Match operation to story

Brand new in-memory object